Answer:
A
Explanation:
The main reason for expanding the borders of America was to gain more land to help the economic structure of America
I'm pretty sure it would be C.)Congress votes to increase the income tax, because that relates to stuff inside the nations borders.
The other options deal with stuff outside of the nations borders.
Hope this helps!
This may help,
http://www.history.com/topics/robert-mugabe
Pashtun would be your answer hope this helps